This invention relates to accessory drive tuning devices with torsion springs for isolation, and in particular, devices with a self-engaging torsion spring locking feature.
This invention relates to accessory drive tuning devices with torsion springs for isolation of vibrations. These devices as commonly known in the art are alternator tuning pulleys and crankshaft tuning devices. Examples of such devices are the alternator isolator decoupler (“AID”) as described for example in U.S. Pat. No. 8,678,157, the alternator isolator pulley (“AIP”) as described for example in U.S. Pat. No. 7,207,910, a crankshaft isolator decoupler (“CID”), the overrunning alternator decoupler (“OAD”) as described for example in U.S. Pat. Appl. Pub. No. 2013/0098727, and the crankshaft isolator pulley sold under the trade name Torqfiltr by Litens. These devices may or may not have a one-way clutch. In either case the spring may exhibit spring rattle. Spring rattle occurs when the spring is allowed to slide in and out of its pocket or away from its stop. The speed fluctuation resulting from the torsional vibration of a firing engine can cause the spring to slide out in the same or opposite direction relative to the rotating direction of the pulley. The re-engagement of the spring in the pocket or against the stop can create a noise that would be unacceptable to the customer.